Calf circumference as a simple tool versus chest-CT derived skeletal muscle index in assessing osteosarcopenia and one-year outcomes in osteoporotic vertebral fractures

BACKGROUND AND AIMS: Osteosarcopenia, the coexistence of osteoporosis and sarcopenia, is underdiagnosed due to limited diagnostic methods despite its strong association with fractures and falls in older adults. This study compared calf circumference (CC) with chest-CT for assessing osteosarcopenia and predicting outcomes in patients with osteoporotic vertebral fractures (OVFs), aiming to assess simpler and more accessible tools for osteosarcopenia in resource-limited settings. METHODS: We studied 149 patients with OVFs who underwent percutaneous vertebroplasty (PVP), using chest-CT (T12 skeletal muscle index, T12 SMI) and CC to diagnose sarcopenia, alongside grip strength (GS) and Short Physical Performance Battery (SPPB) tests. We compared outcomes like re-fractures, falls, Activities of Daily Living (ADL), and Oswestry Disability Index (ODI) scores over one year. RESULTS: Osteosarcopenia prevalence was 47% with chest-CT and 52% with CC, showing moderate agreement (Kappa = 0.60). Osteosarcopenia patients had worse outcomes, including lower ADL, higher ODI, and more re-fractures and falls. CC had high sensitivity (84%) but moderate specificity (76%). Binary logistic regression identified abdominal circumference (AC) as the main factor affecting diagnostic consistency. Osteosarcopenia diagnosed by chest-CT were association with re-fracture in one year. CONCLUSION: Chest-CT derived T12 SMI defined osteosarcopenia is associated with re-fractures in OVF, while CC provides a simple and sensitive screening tool for osteosarcopenia patients, particularly in fracture patients without markedly high AC.